The invention relates to a control device for the focusing element of a microscope, equipped with control knobs which receive a movement of the fingers or the hand of an operator and via gear elements change the focal position relative to a sample to be observed.
During microscoping, the adjustment of the optimal focal position is frequently the first and most important interaction of the operator with the microscope. Thereby, a control element is usually manipulated with an appropriate finger or hand movement, which triggers an adjustment movement and transfers said adjustment movement to a focusing element, e.g., a microscope lens, a lens turret, the sample stage, a tube lens, or an intermediate tube.
It is known that mechanical gear elements are exclusively provided for the transfer of the adjustment movement from the control element to the respective focusing element.
Alternatively to this classic version, it is known that the manually triggered movement of the control element, particularly a control knob, is initially converted into electric signals and that said signals are fed to an electronic control circuit which is connected to a drive motor; only then the movement triggered by the drive motor is transferred to the focusing element via gear elements.
The subsequently described invention is to be categorized in this field of motor-driven focusing.
Motor-driven focusing is especially prevalent in microscopes which are used for sophisticated research applications with the main concern of moving different focal positions with great repeat accuracy within the sub-micrometer range. Furthermore, motor-driven focusing also provides advantages in the area of industrial and biomedical applications with regard to precise and repeated focal adjustments as well as the resulting option of coupling the focusing speed with the respective set magnification of the microscope.
In this context, control devices are known which exhibit two control elements in the form of control knobs, whereby one is intended for manual triggering of a coarse adjustment and the other one for the manual triggering of a fine adjustment during focusing.
Since the adjustment of the focal position requires a delicate and precise, albeit manual movement, the operator needs to be provided with effortless working conditions.
Therefore, development and design of respective control devices always require consideration of the individual needs of the operator as well as a functional and economical design.